Origin of the 44-mm Behind-Armor Blunt Trauma Standard

Hanlon, Erin; Gillich, Patrick J

doi:10.7205/milmed-d-11-00303

Cited by 43 publications

(13 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The numerical simulation results indicate that the BCS is not broken down by pistol cartridge, and the maximum depression depth of skin is 4.98 mm, which is less than 25 mm specified by the Chinese standard [32] and 44 mm specified by the NIJ standard [16]. Hence, the pistol cartridge does not directly shoot the human torso.…”

Section: Resultsmentioning

confidence: 95%

“…According to GA 141-2010 “Police ballistic resistance of body armor” [15], the backing materials (such as clay) are used to simulate the human torso to assess the bulletproof performance of body armor. In the case of a valid hit for bullet, the body armor can block the warhead, and the maximum backface signature is less than or equal to 25 mm, that is, the body armor can effectively protect the killing effect of the pistol cartridge, while the NIJ (National Institute of Justice) standard is 44 mm [16]. It is impossible to ascertain the injury situation of the human wearing the body armor, so the evaluation method is only suitable for evaluating the bulletproof performance of body armor, and it is also difficult to be applied to the evaluation of the protective performance of body armor to the human.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical simulation for behind armor blunt trauma of human torso under non-penetrating ballistic impact

Tang

Guo

Yuan

et al. 2019

Preprint

View full text Add to dashboard Cite

A human torso finite element model with high bio-fidelity was developed to study the 2 behind armor blunt trauma (BABT) of pistol cartridge on human torso with bulletproof composite 3 structure (BCS) and the effect of buffer layer (expandable polyethylene, EPE) on BABT. The 4 bulletproof structure was made of multilayered composite of aluminum alloy (AlSi 10 Mg) and 5 thermoplastic polyurethanes (TPU), and the ANSYS/LS-DYNA software was used to simulate the 6 blunt ballistic impact process of pistol cartridge on human torso. Results indicated that the BCS 7 could resist the shooting speed of 515 m/s without being broken. During the process of pistol 8 cartridge shooting the BCS, the energy of pistol cartridge was transmitted to the human organs 9 through the BCS, thereby causing human injury. Moreover, the mechanical response parameters 10 of various organs were determined by the distance between the human organs and the impact point. 11The sternal fracture and liver rupture were not produced based on the threshold stress of sternum 12 and liver injury, no matter whether the buffer layer was added or not. According to the Axelsson 13 injury model, a slight to moderate injury was created when there was no buffer layer, but the injury 14 level was trace to slight caused by the buffer layer with thickness of 1.0 mm, and the buffer layer 15 with thickness of 2.5 mm and 5.0 mm caused subtle BABT. It was concluded that the buffer layer 16 could effectively reduce the BABT, and the reduction was related to the thickness of the buffer 17 layer. This study reveals the mechanism of the BABT, which can provide a theoretical basis for 18 the design of the bulletproof structure and the evaluation of structural bulletproof performance and 19 protection performance. 20

show abstract

Section: Resultsmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Numerical simulation for behind armor blunt trauma of human torso under non-penetrating ballistic impact

Tang

Guo

Yuan

et al. 2019

Preprint

View full text Add to dashboard Cite

show abstract

“…In addition, gelatine has similar deformation response to Roma Plastilina No. 1 in terms of behind soft armor blunt trauma assessment (Prather et al, 1977;Hanlon and Gillich, 2012). A 250 × 150 × 50 mm gelatine block was put lightly in contact with, and behind, the sample to simulate a realistic boundary condition between the ballistic fabric and the soft tissue.…”

Section: Methodsmentioning

confidence: 99%

Gelatine Backing Affects the Performance of Single-Layer Ballistic-Resistant Materials Against Blast Fragments

Nguyen

Meek

Breeze

et al. 2020

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

Penetrating trauma by energized fragments is the most common injury from explosive devices, the main threat in the contemporary battlefield. Such devices produce projectiles dependent upon their design, including preformed fragments, casings, glass, or stones; these are subsequently energized to high velocities and cause serious injuries to the body. Current body armor focuses on the essential coverage, which is mainly the thoracic and abdominal area, and can be heavy and cumbersome. In addition, there may be coverage gaps that can benefit from the additional protection provided by one or more layers of lightweight ballistic fabrics. This study assessed the performance of single layers of commercially available ballistic protective fabrics such as Kevlar R , Twaron R , and Dyneema R , in both woven and knitted configurations. Experiments were carried out using a custom-built gas-gun system, with a 0.78-g cylindrical steel fragment simulating projectile (FSP) as the impactor, and ballistic gelatine as the backing material. FSP velocity at 50% risk of material perforation, gelatine penetration, and high-risk wounding to soft tissue, as well as the depth of penetration (DoP) against impact velocity and the normalized energy absorption were used as metrics to rank the performance of the materials tested. Additional tests were performed to investigate the effect of not including a soft-tissue simulant backing material on the performance of the fabrics. The results show that a thin layer of ballistic material may offer meaningful protection against the penetration of this FSP. Additionally, it is essential to ensure a biofidelic boundary condition as the protective efficacy of fabrics was markedly altered by a gelatine backing.

show abstract

“…1 (RP1) was reported to have comparable ballistic performance as the gelatin with the advantage that the residual cavity formed in RP1 was easily measured and could provide a value for the BFS. Consequently, the National Institute of Justice (NIJ) and the U.S. Army adopted RP1 as the standard BWM for body armor [1,5,6]. While the performance standards for body armor have undergone periodic revisions, RP1 is still the required BWM [1,6,7].…”

Section: Introductionmentioning

confidence: 99%

Rheological Characterization of Next-Generation Ballistic Witness Materials for Body Armor Testing

et al. 2019

View full text Add to dashboard Cite

Roma Plastilina No. 1 (RP1), an artist modeling clay that has been used as a ballistic clay, is essential for evaluation and certification in standards-based ballistic resistance testing of body armor. It serves as a ballistic witness material (BWM) behind the armor, where the magnitude of the plastic deformation in the clay after a ballistic impact is the figure of merit (known as “backface signature”). RP1 is known to exhibit complex thermomechanical behavior that requires temperature conditioning and frequent performance-based evaluations to verify that its deformation response satisfies requirements. A less complex BWM formulation that allows for room-temperature storage and use as well as a more consistent thermomechanical behavior than RP1 is desired, but a validation based only on ballistic performance would be extensive and expensive to accommodate the different ballistic threats. A framework of lab-scale metrologies for measuring the effects of strain, strain rate, and temperature dependence on mechanical properties are needed to guide BWM development. The current work deals with rheological characterization of a candidate BWM, i.e., silicone composite backing material (SCBM), to understand the fundamental structure–property relationships in comparison to those of RP1. Small-amplitude oscillatory shear frequency sweep experiments were performed at temperatures that ranged from 20 °C to 50 °C to map elastic and damping contributions in the linear elastic regime. Large amplitude oscillatory shear (LAOS) experiments were conducted in the non-linear region and the material response was analyzed in the form of Lissajous curve representations with the values of perfect plastic dissipation ratio reported to identify the degree of plasticity. The results show that the SCBM exhibits dynamic properties that are similar in magnitude to those of temperature-conditioned RP1, but with minimal temperature sensitivity and weaker frequency dependence than RP1. Both SCBM and RP1 are identified as elastoviscoplastic materials, which is particularly important for accurate determination of backface signature in body armor evaluation. The mechanical properties of SCBM show some degree of aging and work history effects. The results from this work demonstrate that the rheological properties of SCBM, at small and large strains, are similar to RP1 with substantial improvements in BWM performance requirements in terms of temperature sensitivity and thixotropy.

show abstract

Origin of the 44-mm Behind-Armor Blunt Trauma Standard

Cited by 43 publications

References 16 publications

Numerical simulation for behind armor blunt trauma of human torso under non-penetrating ballistic impact

Numerical simulation for behind armor blunt trauma of human torso under non-penetrating ballistic impact

Gelatine Backing Affects the Performance of Single-Layer Ballistic-Resistant Materials Against Blast Fragments

Rheological Characterization of Next-Generation Ballistic Witness Materials for Body Armor Testing

Contact Info

Product

Resources

About